1. Field of the Invention
The present invention relates to a system for customizing a sports implement and, more particularly, to a system for customizing various properties relating to the weight and mass distribution of such an implement.
2. Description of the Prior Art
Many sports, such as tennis, golf and baseball, to name a few, require the use of an implement. In sports such as these where the implement is moved by the player to strike a ball, the weight and mass distribution properties of the implement are very important. Not only are those properties themselves of interest to the player, but the ability to duplicate them from one implement to the next can also be important.
The more skilled the player, the more critical it is to be able to control the properties of the implement to within very close limits. For example, in tennis the top players strive not only to find a racket that has properties they like but also to duplicate those properties from one racket to the next. The player may in fact not even understand the physics underlying his or her preferences, expressing them only in terms such as the "feel" of the racket. However, the ability to control the physical properties that impart a particular "feel" is highly desirable in tennis (as well as other sports).
In actuality, the physical properties that top players experience as "feel" are attributable largely to three physical parameters. They are weight, the location of the center of gravity or mass centroid (also called "balance" or "balance point") and moment of inertia (also called "swing weight"). The very best players can detect tiny differences in these properties from one racket to the next, and they are notoriously difficult to reproduce from racket to racket. There are those with sufficient skill and experience to customize a racket with a "feel" that duplicates that of an existing racket, but it is largely an art not easily taught, rather than a science with results that can be repeated independently of an individual racket customizer's skill.
The best system would be one that enabled perfect duplication of the "feel" of a particularly favorite racket of any given player. The difficulty in achieving that goal arises from the fact that even two identical model rackets from the same manufacturer have slight differences that a top player can detect. The differences are attributable in part to variations in the racket blank as manufactured, but they are also due to variations introduced when the handle, grip, overwrap and other components are put on the racket blank to customize the finished racket.
Of course, duplicating racket weight is trivial, since it requires only a scale to weigh the racket and then changing the weight to a desired value using conventional lead tape adhered to the racket frame. There are commercially available machines that measure racket balance as well. Again, it is easy to manipulate balance (center of gravity) also by using lead tape. However, adding weight to adjust the center of gravity will change the weight, and vice versa, and it is this aspect of racket customizing that makes it difficult to duplicate a racket's properties.
Moreover, if swing weight (moment of inertia) is also to be duplicated, another measurement and another criteria for distributing the weight in the racket is added. In that regard, there is no known prior art that provides a simple yet accurate measurement of swing weight together with the ability to customize a racket such that it has a particular desired swing weight. For example, the results achieved with one known machine for measuring swing weight are dependent on the individual operator using the machine. In addition, that machine has inherent inaccuracies because it uses springs, which are dependent on environmental influences and experience changes in their properties over time.
Accordingly, up to now it has been difficult, although possible, to produce a finished racket with the same weight and balance as a reference racket. That is, although there are those who can sometimes produce a racket with a given weight and balance, the ability to do so depends almost exclusively on the skill of the individual undertaking the task. As for duplicating swing weight, the difficulty in accurately measuring this parameter, not to mention the near impossibility of duplicating a reference racket's swing weight as well as its weight and balance, has largely led to those skilled in the art ignoring it as a parameter in racket customizing.
Therefore, even though a player might not appreciate why, to have a favorite racket's feel accurately reproduced has been largely a matter of chance, depending on whether the racket customizer chosen by the player was sufficiently lucky or skilled to have been able to duplicate all three major physical properties contributing to the feel of a reference racket supplied to the customizer by the player.